Thorite
An example of the element Uranium

Thorite.
This is a lovely shiny crystal of thorite, a rare radioactive mineral, from Mt. Zagi, Pakistan. The price reflects the rarity of this species more so than its beauty, though this one is really quite attractive.Source:eBay seller 4jdkContributor:Theodore GrayAcquired:25 September, 2005Price: $76Size: 0.5"Composition: (Th,U)SiO